Bumping gaia.json for 2 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/11e8901eca1c
Author: Dave Hylands <dhylands@gmail.com>
Desc: Merge pull request #12928 from dhylands/dhylands-928097-ums-state

Bug 928097 - Add initial value for ums.state setting. r=gwagner

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https://hg.mozilla.org/integration/gaia-central/rev/8e13d74fe535
Author: Dave Hylands <dhylands@gmail.com>
Desc: Bug 928097 - Add initial value for ums.state setting.